Screw-clamp for stools



(No Model.)

` R. WANGEMAN.

` SCREW CLAMP EUR STOOLS.y No. 274,680. Patented Mar. 27,1883.

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' UNITED dSTATES;

- PATENT OFFICE.

RUDOLPH WANGEMAN, OF SAN FRANCISCO, CALIFORNIA.

SCREW-CLAMP FOR STOOLS.

SPECIFICATION forming part of Letters Patent No. 274,680, dated March 27, ll883.

Application tiled January 9,1883. (No model.) i

To all whom it may concern Be `it known that I, RUDOLPH WANGEMAN, of the city and county of San Francisco, State of California, have invented an Improved Screw-Clamp for Stools; and I hereby declare the following to be aV full, clear, and exact description thereof. f

My invention relates to a new and useful clamp for the screws of vertically-adjustable stools, chairs, &c., the object ot' which is to holdthe screw tightly in its socket to prevent the side play or looseness which is always attendant upon devices of this character.

My invention consists in a wedge-sleeve encircling the screw, which, either by its own 4weight or by the downward pressure of the screw itself, is adapted to be depressed sufficiently in the standard to bind upon and clamp the screw so that it cannot haiie any side play, as will hereinafter particularly appear, reference being made to the accompanying drawings, in which- Figurel isasection through a stool, showing the application of my screw-clamp. Fig. '2 is aperspective View. Fig. 3 is a section through a stool, showing a modied form of my screwclamp. Fig. 4 is `a perspective view of the modification.

Let A represent the standard of a stool, having the usual vertical socket, a, in which is a stationary nut, B, for the reception of the screw C, which is bolted under the seat D in the usual manner. Upon top of the standard Ais screwed an annular disk or rim F, the screw G passing through it. p

E representsV the wedge-sleeve. This consists of two parts or halves having small pins b and sockets b near their tops, which, en-

y gaging, serve t0 keep one part from slipping past the other. (See Fig. 2.) The outer surface of these partsis tapered, the thicker portion being at the top. v This wedge-sleeve fits l around the screw andhan gs downin the socket a through the rim F, its upper end being too large to pass through said rim. The weight ofthe sleeve causes it to wedge in the rim F and thus to bind or clamp the screw C, for the purpose described. It in no wise prevents the easy operation of the screw in its vertical ad- 5o justment, for it embraces said screw loosely,

the rim F and the screw. Thus I avoid the usual looseness of the' screw without having so close-fitting a socket as to prevent its ready adjustment.

A modification of this wedge-sleeve Ishow in Figs. 3, 4, in which the letters indicate similar parts. -In this case the lower endsof the two-part sleeve arek hinged to the nut B by means ofE pivots through ears c on saidput. The nut itself, instead of being fixed in the standard, as heretofore described, hangs loosely therein,*being sustained by the upper ends of the sleeve wed gin g in the rim F. The screw C passes down through the sleeve and nut, as

before; but when-the weight is placed on the.

This clamp, while applicable to stools and chairs of any description in which a screw is t l. In a vertically-adjustable stool, chair,

&c., the standard A, having socket a, with nut B, located midway between top and bottom thereof, and the adjustable screw C, in combination with the tapering sleeve E, located at the top of the standard A, embracing and clamping said screw by wedgingitself between said screw and the wall of the socket a, sub stantially as and for the purpose herein described.

2. In a vertically-adjustable stool, chair, &c., the standard A, having socket .nut B, located midway between top and bottom of said socket, the annular rim F, and the screw C, in combination with the tapering sleeve E, located at the top of the standardA, embracing said screw and clamping or binding it when wedged between the rim F and said screw, substantially as and for the purpose herein described.

8. In a vertically-adjustable stool, chair,

IOO

&e., the standard A, having socket a, the ansaid screw and rim F above, substantially as nular rim F, and the screw C, in combination and for the purpose herein described. with the nut B, loose n socket t and midway In witness whereof I hereunto set my hand. 1o

between top andbottoln thereof, and the taperl RUDOLPH WAN GEMAN. 5 ing sleeve E, located at the top of the standard Witnesses A, hinged below to said nut and adaptedvto E. W. SKILTON,

clamp or bind the screw when wedged between J. H. BLOOD. 

